以吉林汪清林区臭松次生林为对象,分析了臭松次生林的树种组成和直径结构规律。采用威布尔分布(Weibull)、伽马(Gamma)及对数正态分布(logarithmic normal)进行直径拟合并进行卡方检验,研究表明:臭松林分平均直径为15.1cm,最小直径为5.1cm,最大直径为47.1cm,6—28径阶的林木株数所占比重最多,达75.8%,3种分布函数中,威布尔分布的R²为0.997,卡方(χ²)为6.35,拟合效果最好,伽马分布次之,对数正态分布最差,但前两者的差异不大,故威布尔分布和伽马分布适用于臭松林直径结构预测,可为臭松次生林直径结构和林分密度调整提供理论依据。

An analysis was made on the diameter structure of the secondary forest of Adiessibirica Ledeb in the Northeast forest area.The Weibull distribution,Gamma distribution and Log-normal distribution were used for fitting stand diameter distribution and combined with χ² fitting result for examination.The results indicated that the average DBH of Adiessibirica Ledeb forest was 15.1cm,the least diameter class was 5.1cm,the maximum diameter class was 47.1cm,and,the accumulating percentage of diameter class(6-28)was 75.8%.Among the whole distribution functions,the R² Weibull was 0.997,the χ² was 6.35 and the distribution fitting effect is best,followed by the Gamma distribution,the Log-normal distribution was worst,but the difference between the frontal two distributions was similar,all of them can be used to predict Adiessibirica Ledeb diameter structure,which provided theoretical basis for diameter structure and stand density redjustment.